Abstract

Awareness of the importance of Serratia marcescens as an opportunistic pathogen causing nosocomial infections lead us to use deoxyribonuclease and tween 80 hydrolysis tests to identify this organism from our clinical specimens. From 56 patients Serratia marcescens were isolated during the period of February to October, 1977. Among these 56 cases, 43 were reviewed and the following results were obtained. 1. Serratia marcescens were frequently isolated from patients with age groups of both 40-49, and 60 or over. The male to female ratio was 3 : 1. 2. The isolation was frequently from respiratory, woulld and urine specimens. There were two serious patients; one yielded the organism from blood and the other from spinal fluid. 3. The patients yielding the organisms were found to have predisposing factors such as various debilitating disorders, surgical procedures and urinary catheterizations. 4. Thirty eight out of the 43 were hospitalized patients and remaining 5 were outpatients with previous hospitalizations. This fact is highly suggestive of the nosocomial nature of the infections. 5. At the time of bacterial culture, 34 patients had been receiving single or multip!e antibiotics, suggesting the relationship of the infections an4 the antibioic administrations. 6. In 10 patients, the organisms were solely isolated indicating their etiological significance. From the rest of the patients other organisms were also isolated together with Serratia marcescens. Serrtia infections were thought to be rare previously, but it was obviously wrong and perhaps it was due to the difficulty of their correct identification. The infections are frequent among long standing inpatients particulary in aged persons with various underlying disorders. A correct identification and a proper susceptibility testing should be considered imperative for both prevention of new infections and adequate treatment of the patients.